The present invention relates to remote radio controlled mobile toys, and in particular to radio controlled car toys in which the direction of the car is to be altered by a transmitted radio signal. In conventional systems of this type two separate motors are connected to the left and right driving wheels of the car which are driven by the radio wave-detector output of a pulse width modulated high frequency or low frequency signal. The direction of travel of the mobile toy is altered by varying the pulse width of the signal. However, since such devices are pulse width modulated systems, they suffer from the drawbacks of complicated construction, high cost and susceptibility to external noise as well as other disadvantages recognized from the use of pulse width modulated signals.
In the present invention which relates to remote radio controlled mobile toys, a pair of filters, one a high pass frequency filter, the other a low pass frequency filter, have their outputs connected to separate motors, one motor driving the right wheel of the vehicle, the other motor driving the left wheel. As the frequency of the transmitted signal is increased or decreased, the voltage to one of the motors is increased while the voltage to the other motor is decreased, thereby increasing or decreasing the speed of rotation of the respective wheels, resulting in a change in direction of the toy vehicle.
Accordingly, it is an object of the present invention to provide a system for reliably controlling the direction of radio controlled toy vehicles.
It is another object of the present invention to provide a simple and economic circuit for controlling a radio controlled toy vehicle.
It is still another object of the present invention to provide a toy vehicle which can be easily manipulated and controlled.
It is still another object of the invention to provide a circuit for controlling the direction of a radio controlled vehicle which is less susceptible to external noise.
These and other objects of the present invention will be readily appreciated from a reading of the following description of the invention and the accompanying drawings.